22 Studies on Arthropoda. I. 



lateral thorns a kind af sieve for the air. The processes are 

 light brownish. 



In 1904 we showed that in the female of the large form Ciyp- 

 tostemma Afzelii Thor. the sternites of first and second abdo- 

 minal segments are freely movable, crescent-shaped, with their 

 concave margins turning against each other, and they surround 

 together the genital aperture; both sternites are only visible, 

 when the abdomen is bent much upwards. In C. Fcce n. sp. 

 I find the same structure, but the sternites are a little less robust. 

 In this species — and probably in all other forms of the order 

 — the genital aperture is in the male much smaller than in the 

 female; the sternite of second segment is very thin and semi- 

 circular or in reality curved so nmch, that it occupies about 

 three-fifths of a circle; the sternite of first segment is produced 

 downwards as a freely protruding, triangular plate about as 

 long as broad and with the end subacute. The same plate is 

 also found in the adult male of C . crassipalpc. An internal co- 

 pulator}^ organ is, as might be expected, completely wanting, 

 l)ut according to my dissection of a single male, the inner sexual 

 organs and the alimentar}- canal can scarcely be made out 

 with certainty without fresh material or at least the sacrifice 

 of several well preserved specimens of both sexes. 



The Larva. — The body is about 2.3 mm. long, second 

 leg 3.3 mm. In general aspect the body of the larva is in the 

 main similar to half-grown specimens, differing in being compa- 

 ratively a little broader, with the grooves on cephalothorax 

 partly feebly developed, partly wanting, and without grooves 

 on the cucullus, while the tergites of the abdomen and the gra- 

 nulation are nearly as in postlarval younger stages. But the 

 larva has only three pairs of walking legs, as the 

 fourth pair is completely wanting (pi. Ill, fig. i g). 

 That it is the fourth pair which is wanting is seen from 

 the fact, that the coxtc of first, second, and third pairs 



